Liquid crystal driver and optical head for tilt correction
US7031247B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 2003 |
| Grant date | Apr 18, 2006 |
| Priority date | — |
| Expiry date | Oct 13, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2320/0247
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Tilt which is inclination of a normal of optical disk relative to optical axis of optical head is corrected with a liquid crystal element. In a driver for the liquid crystal element, a periodic waveform generator generates periodic waveform and an inverting element inverts the periodic waveform. The periodic waveform and the inverted waveform are connected to two ends of a potential divider which provides partial voltages. The periodic waveform is connected to a common electrode of the liquid crystal element, and the partial voltages of the potential divider are connected to electrodes opposing the common electrode. A structure of a driver circuit for each direction is simple. Tilt in a plurality of directions can be performed independently of each other. Spherical aberration is also corrected. When the liquid crystal element is mounted to a fixed component, deterioration due to jitters is reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.